The present invention relates in general to test equipment and, more particularly, to diagnostic, test, and information systems. Specifically, one embodiment of the invention is directed to a modular wireless diagnostic, test, and information system comprising a combined user interface and main control module and at least one remotely controlled instrumentation module connected by wireless communication. The combined user interface and main control module has an interactive display which enables the user to command the functions of the remotely deployed instrumentation module(s) and enter data through interaction with the display, as well as executes application programs and displays information to the user. For example, one embodiment of the invention provides a combined user interface and main control module having an interactive display, in which the user interacts with the display to access complex technical information employed to maintain and repair a motor vehicle and to control the instrumentation module(s) over a wireless communication link in the form of a radio-frequency (RF) local area network (LAN) to perform measurements on the vehicle, as well as to execute diagnostic routines and to display information to the user. Such a modular wireless motor vehicle diagnostic, test, and instrumentation system is particularly useful to provide information about a motor vehicle and vehicle diagnostics to the user during maintenance or repair of the vehicle.
Although the modular wireless diagnostic, test, and information system in accordance with the invention is susceptible to being used in various applications, it has been found to be particularly advantageous for use in the maintenance and repair of motor vehicles. Therefore, an embodiment of the modular wireless diagnostic, test, and information system in accordance with the invention will be described in connection with service of a motor vehicle. However, it is to be understood that the invention is not limited to motor vehicle maintenance and repair and may also be applicable to non-motor-vehicle applications.
Today, there are various handheld testers used in connection with the maintenance and repair of motor vehicles. Typically, these testers comprise cables attached to a microprocessor-based handheld device. The cables, for example, include a cable that connects to the motor vehicle battery and another cable that connects to an electrical system or component of the motor vehicle to measure voltage and current, as well as a data cable that connects to the engine control module to transmit information about operation of the vehicle to the handheld tester or to enable the tester to control various motor vehicle functions. See, for example, Tech 1, "Cartridges and Accessories," September, 1989.
Unfortunately, the cables connected to the motor vehicle are typically heavy and stiff. Consequently, the handheld tester is unwieldy to operate, which is inconvenient for the user. Furthermore, the display screen on the handheld tester is typically small, and, therefore, only a minimal amount of information can be displayed to the user.
Regarding the display of information to the user, the trend in the motor vehicle service bay is toward greater access to information relating to maintenance and repair. This trend requires the user to have a larger display screen incorporated into his or her test equipment and many connections to the motor vehicle, as well as to a dealership local area network (LAN).
Historically, motor vehicle manufacturers have provided printed information regarding maintenance and repair. As a service to motor vehicle maintenance and repair personnel, the manufacturers provided published information, such as manuals, for reference during maintenance and repair of motor vehicles. However, published information requires a large amount of storage space.
More recently, motor vehicle manufacturers have provided maintenance and repair information on microfiche which is periodically updated. Although microfiche reduces storage requirements, microfiche can be misfiled, and microfiche readers are cumbersome to use.
Today, various computer-based systems exist for providing motor vehicle maintenance and repair information. Some of these computer-based systems also comprise instruments to perform measurements in connection with motor vehicle evaluation and diagnosis. For example, one such computer-based system is the Model HP 27070B ("TestBook"), available from Hewlett-Packard Company, Palo Alto, Calif. See, "HP TestBook," Hewlett-Packard Company Part No. 5091-9697E, September, 1993.
The TestBook system is a portable integrated personal computer and test system that provides a compact mobile test and information tool for use in the motor vehicle service bay or on a road test. The TestBook system comprises a 486-microprocessor-based personal computer, an integrated adjustable VGA liquid crystal display (LCD) panel and touchscreen interactive user interface having a capacitive touch-activated screen, and a built-in CD-ROM drive to provide faster and easier access to the latest service procedures and information for maintenance and repair of a motor vehicle. Built-in measurement instrumentation and a programmable communications interface offer a test capability for computer-aided diagnostic applications. The TestBook system can be custom-configured to meet various MS-DOS, Windows, or OS/2 application requirements.
While the TestBook system provides ready access to a large amount of information needed for maintenance and repair of a motor vehicle, cables that connect to the vehicle must be attached to the measurement instrumentation integrated into the system. Consequently, as in the case of handheld testers, the TestBook system is unwieldy and is typically set on a work surface, such as a workbench or tool chest, during use. Therefore, the user does not have ready access to the integrated interactive display of the TestBook system while he or she is under the hood of the motor vehicle.
Additionally, a test and information tool for maintenance and repair of a motor vehicle, which has a selectively detachable, remotely operated interactive display unit that controls a portable integrated personal computer and test system is disclosed in co-pending U.S. patent application Series Code/Ser. No. 08/421,591, filed on Apr. 12, 1995, and assigned to the same assignee as the present application. This motor vehicle test and information tool provides greater user mobility than the TestBook system, because the display unit is not encumbered by being integrated with the personal computer having the additional weight of measurement instrumentation tethered by cables connected to electrical systems and components, as well as the engine control module, of the motor vehicle.
However, the measurement instrumentation is integrated with the personal computer, which requires a specially designed housing to accommodate both the personal computer and measurement instrumentation. The integrated personal computer and measurement instrumentation must also meet environmental and safety requirements relating to test equipment used in a motor vehicle service bay.
It is therefore desirable to provide a system to facilitate access to information by a user during maintenance and repair of a motor vehicle. Additionally, it would be desirable to enable the user to control the display of information about maintenance and repair of a motor vehicle and perform needed measurements, as well as display information to the user, while he or she is under the hood of the vehicle. It would be further desirable to have an interactive information display and control system that is not encumbered by cables connected to the motor vehicle. Also, it would be desirable to have a diagnostic, test, and information system that is easily scalable by the selection of any desired amount of measurement instrumentation. Furthermore, it would be desirable to provide a diagnostic, test, and information system which minimizes both the number of specially designed components and the number of components subjected to the harsh environment and safety requirements for equipment used in a motor vehicle service bay.